Flashcards in APP GI and LIver Deck (53)
List the risk factors associated with GERD
3. Nervous system injury
5. Delayed gastric emptying
6. Hiatal hernia
7. Physiological GERD: eating a big meal, reclining, etc.
What is hiatal hernia?
when your stomach is up in your throax - the LES is surrounded by the diaphragm, which partly helps it maintain its tone. If the LES is pushed up into the thorax, you aren't going to get as much constriction of the sphincter
List the 4 complications associated with GERD
3. Barrett Esophagus
Which patients need an endoscopy to check for GERD?
Patients with multiple risk factors for Barret's/Cancer: white male, >50 years old, chronic GERD, obesity, etc.
Describe how the loss of neurons can result in Achalasia
1. There are two types of neurons in the plexus that controls the smooth muscle: inhibitory neurons (inhibit the muscle - muscle relaxes) and stimulatory neurons (cause the muscle to constrict)
2. Preferential loss of inhibitory neurons in the myenteric plexus
What do we see with the Manometry study that proves it is Achalasia?
the resting tone is elevated - the tone doesn't decrease with swallow
What is a key indicator of Pyloric Stenosis?
non-bilious because of the obstruction
Explain how blood travels through the liver
1. The blood that is coming in from your portal vein and hepatic vein are going to come in to these outside artery and vein branches on each of the lobules and they will then send branches through the lobules to that central blood vessel
2. As these blood vessels send blood through these canals, they are going to be lined by hepatocytes (where a lot of the liver filtration system is happening)
List the functions of the liver
1. Regulation of carbohydrate, lipid, and protein metabolism
2. Regulation of cholesterol production
3. Beta-oxidation of fatty acids - breakdown of fats
4. Endocrine - make angiotensin, albumin, insulin-like growth factor, metabolizing hormones in the liver, etc.
6. Vitamin and iron storage
What type of hormone do we mainly metabolize in the liver?
List the 3 key things you expect to see in the blood of patients with liver failure
3. Coagulation defects
Why do you expect to see anemia in patients with liver failure?
Because we lose our iron stores - prevents us from making new blood cells
What is thrombocytopenia?
low platelet count; thrombopoietin is a hormone made in the liver that tells bone marrow to produce platelets
Why do we see gonadal disturbances with liver failure?
the liver is responsible for metabolism of steroid hormones
With liver failure there are high levels of testosterone and estrogen
What happens when there is a decrease in aldosterone metabolism?
Increased salt and water retention, hypokalemia
List the skin disorders that are associated with liver failure
2. Vascular spiders
3. Palmar erythema
What are vascular spiders and what causes them?
1. Vascular Spiders: on the skin, there is an arteriole that dilates and all of the arterioles and venules coming around it will also dilate --> it looks like a circle with these "little legs coming off of it"
2. Caused by high levels of estrogen
When do we see Hepatorenal Syndrome?
acute renal failure that is commonly seen during the terminal stages of liver failure
What causes Hepatorenal Syndrome?
1. The cause of this is not changes to the kidney itself - the kidney is actually totally functioning
2. In the end stages of liver failure, the liver begins to change the patterns of blood flow in the body --> causes a significant decrease in blood flow to the kidneys
3. The kidneys are suddenly getting hyperperfused, resulting in acute renal failure --> this is the prerenal renal failure
How do you characterize hepatorenal syndrome?
1. Progressive azotemia
2. Increased serum creatinine levels
Describe Hepatic Encephalopathy
1. You make ammonia all over your body: the gut makes ammonia, the muscles make ammonia, etc. as part of the metabolism
1a. That ammonia all goes to the liver, and through the urea cycle that ammonia is converted to urea
1b. Urea is a non-toxic substance that gets excreted in the urine
2. In liver failure, the hepatocytes aren't functioning so the ammonia is not converted into urea --> ammonia levels rise
2a. That ammonia is converted in the CNS and muscles to glutamine
2b. Glutamine is a potent neurotransmitter --> there is inappropriate firing of neurons when glutamine is present
Syndrome of shortness of breath and hypoxemia caused by vasodilation of the lungs of patients with liver disease
Mechanism unknown but increased NO production by the lungs is a key mediator
What are the 4 causes of jaundice?
Abnormally high accumulation of bilirubin in the blood
1. Excessive destruction of RBC
2. Impaired uptake of bilirubin
3. Decreased conjugation of bilirubin
4. Obstruction of bile flow
Describe the breakdown of red blood cells into bilirubin
1. Our blood cells come into the Reticuloendothelial System and are broken down into globin and heme
1a. Globin is just a protein so it is broken down into amino acids and recycled back to the body
1b. Heme is broken down by heme oxidase into biliverdin
2. Biliverdin is reduced by biliverdin reductase into bilirubin
2a. Bilirubin will be released into the bloodstream - because it is insoluble, it is carried by albumin to the liver
3. Once bilirubin gets to the liver, it is conjugated with glucuronic acid to form bile, which is sent to the small intestine
What happens once bile is in the small intestine?
1. Some of it gets unconjugated by bacterial beta-glucuronidases
2. Some of it gets turned into urobilinogen --> the kidneys are able to secrete this form into the urine
3. Some of it is sent out in the feces
4. Some of it gets sent to the blood stream
Describe the causes of pre-hepatic hemolysis
the result of excess hemolysis
1. Hemolytic blood transfusion - when you are transfused with the wrong blood type
2. Sickle cell anemia - lyse the sickle cells
3. Hemolytic disease of a newborn - extremely common in newborns: part of it is that the lifespan of red blood cells is shorter for them (turned over quicker, higher amount of hemolysis)
4. Autoimmune hemolytic anemia: you are going to lyse the sickle cells
5. Dyserythropoiesis: when you make bad red blood cells - your body recognized them as sucky and attacks them
Disorders that directly affect the ability of the liver to remove bilirubin from the blood or conjugate it so it can be eliminated in the bile
What does intrahepatic jaundice usually present with?
What are the common causes of intrahepatic jaundice?
2. Cirrhosis = fibrosis
3. Cancer of the liver